1. Field of the Invention
The present invention relates to optical disc recording and reproducing technology, and more particularly, to a method of verifying defect management area information of a recordable and reproducible optical disc upon initialization without certification, and a test apparatus for performing the same.
2. Description of the Related Art
Digital versatile disc-random access memory (DVD-RAM) discs have a defect management function of replacing defective areas with normal recordable areas, and storing information necessary for the defect management in a portion referred to as a defect management area (DMA) thereon. DMA information is repeatedly recorded in four portions on a disc: two portions in a lead-in area and two portions in a lead-out area. DMA information is composed of a disc definition structure (DDS), a primary defect list (PDL) and a secondary defect list (SDL).
DMA information includes information on a spare area and important information on the start logical sector number of each zone, in addition to information on defects, which are detected during certification performed while a disc is being initialized or during use of a disc.
Some information included in the DMA can be immediately read and used. On the other hand, the DMA includes information, which varies with the positions and the number of defects on a disc. That is, some information, for example, the position information of the start logical sector number of each zone or the position information of a first logical sector number, can be obtained only by performing complex computation according to a given algorithm based on defect information registered in the DMA.
Since such DMA information is closely related to a physical data recording position, a recording medium such as an optical disc, which can be used in a given recording and reproducing apparatus even if DMA information on the disc has been generated or updated in another recording and reproducing apparatus, may not be compatible with both recording and reproducing apparatuses when the DMA information is wrong. To overcome this problem, an apparatus and method of verifying that a recording and reproducing apparatus correctly reads DMA information from a disc and correctly records DMA information on the disc is desired.
To solve the above problem, a first object of the present invention is to provide a method of verifying that defect management area (DMA) information is correctly generated upon initialization without certification in an optical disc recording and reproducing apparatus.
A second object of the present invention is to provide a method of verifying that DMA information is correctly generated upon initialization without certification in a recording and reproducing apparatus for repeatedly recordable and reproducible DVD-DRAM discs.
A third object of the present invention is to provide a test apparatus for verifying that DMA information is correctly generated upon initialization without certification in an optical disc recording and reproducing apparatus.
Additional objects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
To achieve the above and other objects of the invention, there is provided a method of verifying that DMA information is properly generated in a recording and reproducing apparatus which records or reproduces information on or from an optical disc with DMA information. The method includes generating as test information, defect management information, which is generated after performing initialization without certification on a blank test disc to which no data is written, and verifying the test information using reference test information for the initialization without certification to provide the test result.
To further achieve the above and other objects of the invention, there is also provided an apparatus for testing a recording and reproducing apparatus which records or reproduces information on or from a recordable and reproducible optical disc with DMA information, to check whether the DMA information is properly generated. The apparatus includes a modified drive unit which generates test information from the DMA information of the test disc, which is obtained after the recording and reproducing apparatus performs initialization without certification on a blank test disc to which no data is written; and a verifier which verifies a test result by verifying the test information using reference test information for initialization without certification.